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Formation of bis-azomethines from hydrazine and heterocyclic aromatic carbaldehydes, namely pyridine-2-carbaldehyde and pyrazine-2-carbaldehyde, is studied using density functional theory. The theoretical investigation is correlated with experimental results obtained by means of NMR spectroscopy. The presence of bis-hemiaminal intermediates is evidenced by NMR spectra while surprisingly stable hemiaminal intermediate was isolated experimentally. Water, methanol and acetic acid were outlined to play a crucial role as active catalysts of elementary steps of the reaction mechanisms. The possible reaction sequences, i.e. addition-dehydration-addition-dehydration or addition-addition-dehydration-dehydration are investigated and discussed. Also, alternative mechanistic path via ionic mechanism was proposed for the formation of hemiaminals. [ABSTRACT FROM AUTHOR]

The synthesis of N‐arylhydroxylamines through the in‐situ hydrogenation of nitroarenes over commercial Pt/C catalyst was investigated. The effects of various reaction conditions including hydrogen donor, solvent, catalyst dosage, temperature and reaction time on the selective hydrogenation of nitrobenzene (NB) to N‐phenylhydroxylamine (PHA) were systematically investigated. The results showed that the yield of N‐phenylhydroxylamine reached 87.2 % using hydrazine hydrate as hydrogen donor in N,N‐dimethylformamide solvent at 30 °C for 60 min. And the catalyst showed no obvious activity loss after a 6‐times recycle. Meanwhile, the developed methodology can also transform a range of nitroarenes to the corresponding N‐arylhydroxylamines in excellent yields (74–99 %). [ABSTRACT FROM AUTHOR]

A mixture of nonlabeled (14N2H4) and 15N labeled hydrazine (15N2H4) in an aqueous solution is oxidized to 15N2, 14N2, and 14N15N molecules, indicating the intermediate existence of the 14NH2-14NH-15NH-15NH2 with subsequent hydrogen transfers and splitting of side N-N bonds. The structures, thermodynamics and electron characteristics of various N4H6 molecules in aqueous solutions are investigated using theoretical treatment at the CCSD/cc-pVTZ level of theory to explain the crucial part of the hydrazine oxidation reaction. Most N4H6 structures in aqueous solutions are decomposed during geometry optimization. Splitting the bond between central nitrogen atoms is the most frequent method, but the breakaway of the side nitrogen is energetically the most preferred one. The N-N fissions are enabled by suitable hydrogen rearrangements. Gibbs free energy data indicate the dominant abundance of NH3... N2... NH3 species. The side N atoms have very high negative charges, which should support hydrogen transfers in aqueous solutions. The only stable cyclo-(NH)4...H2 structure has a Gibbs energy that is too high and breaks the H2 molecule. The remaining initial cyclic structures are split into hydrazine and HN≡NH or H2N≡N species, and their relative abundance in aqueous solutions is vanishing. [ABSTRACT FROM AUTHOR]

The effective mineralization of nitrofurazone (10–100 mg L−1) was performed in aqueous solutions in the presence of chloride ions by electrochemical treatment. The destruction of the organic pollutant molecules was due to their interaction with active oxygen- and chlorine-containing species forming at the inert anode (Pt/Ti or BDD) during electrolysis. Measurements of nitrofurazone concentration, chemical oxygen demand (COD) and total organic carbon (TOC) were used to estimate the removal efficiency of the pollutant. Both the pollutant oxidation rate and the degree of its mineralization were higher for the BDD anode due to the higher anode potentials on it in the course of electrolysis, which provides a high rate of active oxidizer species generation. As a result, practically full nitrofurazone molecule destruction (>99%) was achieved in 30 min at an anodic current density of 0.1 A cm−2, a volume current density of 1.33 A L−1 and pH 2 using BDD anodes. On the other hand, the nitrafurazone degradation efficiency was about 95% for Pt/Ti anodes under the same conditions. Additionally, byproducts of nitrofurazone electrooxidation were investigated by means of liquid chromato-mass-spectrometry (LC/MS). It was found that the initial decolorization of nitrofurazone solution, which occurs during the first 5 min of electrolysis, is due to the formation of a dichloro derivative of nitrofurazone, which causes the destruction of the π−conjugated bond system. Further electrolysis resulted in the almost complete destruction of the dichloro derivative within 30 min of electrochemical treatment. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru)—a high-melting-point precious metal—has attracted attention for use as ultrafine interconnections in large-scale integrations. This is because the resistivity of Ru interconnects is not expected to increase with a reduction in the interconnect width owing to their short mean free path for electrons. In this study, we investigated electroless plating of Ru using hydrazine hydrate as a reducing agent to obtain low-resistivity Ru films. We obtained polycrystalline Ru films on a thin (10-nm) catalytic chemical-vapor-deposited Ru underlayer. The electroless Ru films exhibited significant grain growth upon annealing at 600°C in a forming gas (N2:H2 = 9:1). The Ru (101) and (100) crystalline orientations were strengthened by annealing, and the resistivity decreased from 160 µΩ cm to 22 µΩ cm concomitantly. Thermal desorption spectroscopy showed that the electroless Ru films contained impurities, such as CO, CO2, NH3, O, C, and H2. Desorption of C, CO, CO2, and NH3 showed peak maxima at approximately 450–500 K. These impurity molecules likely came from the inclusion of the complexing agents (tartaric acid: C4(OH)4O2, and ammonium chloride: NH4Cl) and reducing agent (hydrazine: N2H2) into the Ru film. Desorption of these molecules during annealing may improve the grain growth of polycrystalline Ru and reduce its resistivity. [ABSTRACT FROM AUTHOR]

BackgroundProteasome inhibitors (PIs), including carfilzomib, potentiate the activity of selinexor, a novel, first-in-class, oral selective inhibitor of nuclear export (SINE) compound, in preclinical models of multiple myeloma (MM).MethodsThe safety, efficacy, maximum-tolerated dose (MTD) and recommended phase 2 dose (RP2D) of selinexor (80 or 100 mg) + carfilzomib (56 or 70 mg/m2) + dexamethasone (40 mg) (XKd) once weekly (QW) was evaluated in patients with relapsed refractory MM (RRMM) not refractory to carfilzomib.ResultsThirty-two patients, median prior therapies 4 (range, 1-8), were enrolled. MM was triple-class refractory in 38% of patients and 53% of patients had high-risk cytogenetics del(17p), t(4;14), t(14;16) and/or gain 1q. Common treatment-related adverse events (all/Grade 3) were thrombocytopenia 72%/47% (G3 and G4), nausea 72%/6%, anaemia 53%/19% and fatigue 53%/9%, all expected and manageable with supportive care and dose modifications. MTD and RP2D were identified as selinexor 80 mg, carfilzomib 56 mg/m2, and dexamethasone 40 mg, all QW. The overall response rate was 78% including 14 (44%) ≥ very good partial responses. Median progression-free survival was 15 months.ConclusionsWeekly XKd is highly effective and well-tolerated. These data support further investigation of XKd in patients with MM.

It was shown that the reaction of 2-cyanothioacetamides with hydrazine involves both cyano- and thioamide groups, and 3,5-diaminopyrazoles are formed. In the reaction of 2-cyano-3-(dimethylamino)-N,N-dimethylprop-2-enethioamides with hydrazine and its derivatives, the interaction proceeds with the participation of cyano- and enamine groups, not affecting the thiocarbamoyl group, and leads to the formation of 4-thiocarbamoylpyrazoles. A synthesis method has been developed and a series of 1-substituted-4-thiocarbamoyl pyrazoles has been thus synthesized. The structure of the reaction products was studied using NMR spectroscopy and mass spectrometry and confirmed by X-ray diffraction analysis.

Triacsins are an intriguing class of specialized metabolites possessing a conserved N-hydroxytriazene moiety not found in any other known natural products. Triacsins are notable as potent acyl-CoA synthetase inhibitors in lipid metabolism, yet their biosynthesis has remained elusive. Through extensive mutagenesis and biochemical studies, we here report all enzymes required to construct and install the N-hydroxytriazene pharmacophore of triacsins. Two distinct ATP-dependent enzymes were revealed to catalyze the two consecutive N-N bond formation reactions, including a glycine-utilizing, hydrazine-forming enzyme (Tri28) and a nitrite-utilizing, N-nitrosating enzyme (Tri17). This study paves the way for future mechanistic interrogation and biocatalytic application of enzymes for N-N bond formation.

[Display omitted] Recyclization of N -arylitaconimides with hydrazine in dioxane at room temperature selectively leads to 2-(3-oxopyrazolidin- 4-yl)acetanilide derivatives in moderate to good yields. The similar reaction with phenylhydrazine proceeds with the simultaneous formation of isomeric 3- and 5-oxo- 1-phenylpyrazolidine-containing acetanilides. [ABSTRACT FROM AUTHOR]

In the phase 3 BOSTON study, patients with multiple myeloma (MM) after 1-3 prior regimens were randomized to once-weekly selinexor (an oral inhibitor of exportin 1 [XPO1]) plus bortezomib-dexamethasone (XVd) or twice-weekly bortezomib-dexamethasone (Vd). Compared with Vd, XVd was associated with significant improvements in median progression-free survival (PFS), overall response rate (ORR), and lower rates of peripheral neuropathy, with trends in overall survival (OS) favoring XVd. In BOSTON, 141 (35.1%) patients had MM with high-risk (presence of del[17p], t[4;14], t[14;16], or ≥4 copies of amp1q21) cytogenetics (XVd, n = 70; Vd, n = 71), and 261 (64.9%) exhibited standard-risk cytogenetics (XVd, n = 125; Vd, n = 136). Among patients with high-risk MM, median PFS was 12.91 months for XVd and 8.61 months for Vd (HR, 0.73 [95% CI, (0.4673, 1.1406)], p = 0.082), and ORRs were 78.6% and 57.7%, respectively (OR 2.68; p = 0.004). In the standard-risk subgroup, median PFS was 16.62 months for XVd and 9.46 months for Vd (HR 0.61; p = 0.004), and ORRs were 75.2% and 64.7%, respectively (OR 1.65; p = 0.033). The safety profiles of XVd and Vd in both subgroups were consistent with the overall population. These data suggest that selinexor can confer benefits to patients with MM regardless of cytogenetic risk. ClinicalTrials.gov identifier: NCT03110562.

IntroductionImmune thrombocytopaenia (ITP) is an acquired disorder of low platelets and risk of bleeding. Although many children can be observed until spontaneous remission, others require treatment due to bleeding or impact on health-related quality of life. Standard first-line therapies for those who need intervention include corticosteroids, intravenous immunoglobulin and anti-D globulin, though response to these agents may be only transient. Eltrombopag is an oral thrombopoietin receptor agonist approved for children with chronic ITP who have had an insufficient response to corticosteroids, intravenous immunoglobulin or splenectomy. This protocol paper describes an ongoing open-label, randomised trial comparing eltrombopag to standard first-line management in children with newly diagnosed ITP.Methods and analysisRandomised treatment assignment is 2:1 for eltrombopag versus standard first-line management and is stratified by age and by prior treatment. The primary endpoint of the study is platelet response, defined as ≥3 of 4 weeks with platelets >50×109/L during weeks 6-12 of therapy. Secondary outcomes include number of rescue therapies needed during the first 12 weeks, proportion of patients who do not need ongoing treatment at 12 weeks and 6 months, proportion of patients with a treatment response at 1 year, and number of second-line therapies used in weeks 13-52, as well as changes in regulatory T cells, iron studies, bleeding, health-related quality of life and fatigue. A planned sample size of up to 162 randomised paediatric patients will be enrolled over 2 years at 20 sites.Ethics and disseminationThe study has been approved by the centralised Baylor University Institutional Review Board. The results are expected to be published in 2023.Trial registration numberNCT03939637.

A convenient approach to substituted pyrazoles and pyridazinones based on 1,2,4-triketones is presented. Chemo- and regiocontrol in condensations of t-Bu, Ph-, 2-thienyl-, and CO2Et-substituted 1,2,4-triketone analogs with hydrazines are described. The direction of preferential nucleophilic attack was shown to be switched depending on the substituent nature in triketone as well as the reaction conditions. The acid and temperature effects on the selectivity of condensations were revealed. Regiochemistry of heterocyclic core formation was confirmed by NMR and XRD studies. The facile construction of heterocyclic motifs bearing acetyl and (or) carbethoxy groups suggests them as promising mono- or bifunctional building blocks for subsequent transformations. [ABSTRACT FROM AUTHOR]

Keywords: electrochemical synthesis; esterification; aroylhydrazides; reagent-free reaction; anode oxidation EN electrochemical synthesis esterification aroylhydrazides reagent-free reaction anode oxidation 3005 3012 8 08/31/23 20230915 NES 230915 Graph The significance of developing practical and green synthetic methodologies for the ready assembly of diverse ester frameworks cannot be overstated, [1] especially when making allowance for their wide application in medicinal chemistry as well as materials science research. [27] Other groups, including Boydston and co-workers and Shaikh and co-workers, have also developed methods for carboxylic ester synthesis with various substrates via electro-oxidation or electro-reduction processes. Electrochemical synthesis, esterification, aroylhydrazides, reagent-free reaction, anode oxidation The oxidation onset of 4-bromobenzohydrazide ( B 1a b ) was observed at 0.30 V (vs SCE) (Figure 1) and methanol did not show an oxidation peak in the range of 0-1.50 V (vs SCE). [Extracted from the article]

Highlights: The [W–O] group with strong adsorption capacity is introduced into CoP to fabricate a bi-functional catalyst towards HER and HzOR. The cell voltage of HzOR coupled electrolyzer with 6W–O–CoP/NF as both anode and cathode catalysts is 1.634 V lower than that of the water splitting system at 100 mA cm−2. A proof-of-concept self-powered H2 production system is assembled to realize the H2 evolution rate of 3.53 mmol cm−2 h−1. Hydrazine oxidation reaction (HzOR) assisted hydrogen evolution reaction (HER) offers a feasible path for low power consumption to hydrogen production. Unfortunately however, the total electrooxidation of hydrazine in anode and the dissociation kinetics of water in cathode are critically depend on the interaction between the reaction intermediates and surface of catalysts, which are still challenging due to the totally different catalytic mechanisms. Herein, the [W–O] group with strong adsorption capacity is introduced into CoP nanoflakes to fabricate bifunctional catalyst, which possesses excellent catalytic performances towards both HER (185.60 mV at 1000 mA cm−2) and HzOR (78.99 mV at 10,00 mA cm−2) with the overall electrolyzer potential of 1.634 V lower than that of the water splitting system at 100 mA cm−2. The introduction of [W–O] groups, working as the adsorption sites for H2O dissociation and N2H4 dehydrogenation, leads to the formation of porous structure on CoP nanoflakes and regulates the electronic structure of Co through the linked O in [W–O] group as well, resultantly boosting the hydrogen production and HzOR. Moreover, a proof-of-concept direct hydrazine fuel cell-powered H2 production system has been assembled, realizing H2 evolution at a rate of 3.53 mmol cm−2 h−1 at room temperature without external electricity supply. [ABSTRACT FROM AUTHOR]

The reactivity of bis(2‐chloroprop‐2‐enyl)sulfide in the system hydrazine hydrate/alkali has been studied using quantum‐chemical methods. The B2PLYP‐D2//B3LYP approach shows a good agreement between the relative values of activation barriers compared to high‐precision CBS//Q‐B3. The correction for the entropy change during the transition from the gas phase to the binary solvent hydrazine hydrate is calculated. The IEF PCM model was parameterized for hydrazine hydrate solvent. The studied reaction routes includes (i) a competition between migration of the C=C bond and dehydrochlorination of bis(2‐chloroprop‐2‐enyl)sulfide; (ii) 1,3‐prototropic rearrangements of bis (allenyl)sulfide resulting from a dehydrochlorination; (iii) the possible substitution of sulfur and chlorine atoms with hydrazine. The probable formation of the thiiranium and thiirenium cations formation in the above has also been evaluated. [ABSTRACT FROM AUTHOR]

Providing an efficient and low-cost electrocatalyst is one of the most significant challenges researchers facing in direct hydrazine fuel cells (DHFC). Firstly, synthesis of NaY nanozeolite was performed and ion exchanged with 1.0-M Mn(II) nitrate solution to obtain Mn(II)-Y nanozeolite. After identification of sample by XRD, FT-IR, SEM, and BET techniques, the Mn(II)-Y was utilized for amendment of carbon paste electrode to obtain Mn(II)-Y/CPE. The prepared Mn(II)-Y/CPE was utilized for electrocatalytic oxidation of hydrazine in 0.5 M of NaOH that Mn(II)-Y delivers active sites for hydrazine oxidation because of the increasing active surface area and mesoporous structure of Mn(II)-Y. Significant decrease in overvoltage of N2H4 electro-oxidation by this modified electrode against bare CPE is observed. The diffusion coefficients, catalytic rate constant, and surface coverage were attained to be 1.42 × 10–6 cm2 s−1, 1.19 × 104 cm3 mol−1 s−1, and 7.46 × 10−8 mol cm−2, respectively. Overall reaction mechanism indicated creation of ecologically friendly N2 and H2O as ending products. [ABSTRACT FROM AUTHOR]

The [1,2,4]triazolo[4,3-a]pyridine derivative 3-(4-(benzyloxy)-3-methoxyphenyl)-[1,2,4]triazolo[4,3-a]pyridine was prepared in a 73% isolated yield by means of an oxidative ring closure of a hydrazine intermediate. Sodium hypochlorite was used as the oxidant and ethanol as a solvent, making the process a clean, green approach. The reaction was performed at room temperature for 3 h, and then the heterocycle was isolated in an analytically pure form by extraction, followed by passing the crude product mixture through a small plug of alumina. [ABSTRACT FROM AUTHOR]

In order to study the reaction mechanism of hydrazine fuels induced by CO2 at low temperatures, quantum chemical calculations were used to analyze the reaction processes and potential energy surfaces of hydrazine (N2H4), methyl hydrazine (MMH) and unsymmetrical dimethyl hydrazine (UDMH) with CO2 at different temperatures. The reactive sites of N2H4, MMH and UDMH were predicted by using average local ionization energy (ALIE) and Fukui function/dual descriptor. To construct the channel potential energy surfaces, the transition state theory was used to obtain the reaction pathways of different hydrazine fuels with CO2. Thermodynamic parameters and kinetic data in a wide temperature range were obtained according to high precision energy. Results show that the active site of N2H4 is the N atom, the active site of MMH is the N atom attached to methyl group, and the active site of UDMH is the N atom in amino group. The main product of the reaction of hydrazine fuels induced by CO2 is hydrazine carboxylic acid at low temperatures. This reaction is a low temperature forward and high temperature backward reaction, which shows the opposite characteristics to the conventional fuel reactions. The forward and backward reaction transition temperature of N2H4 at 10MPa is the lowest, about 400K, and the corresponding temperature of MMH is about 460 K. UDMH is difficult to react with CO2. The reaction rate constants of hydrazine fuels with CO2 increase with increasing temperature, and the reaction rate constant of MMH is the largest with a value of 3. 51 x 10-8L/(s ⋅ mol) at 10MPa and 453 K. [ABSTRACT FROM AUTHOR]

Water electrolysis for H2 production is restricted by the sluggish oxygen evolution reaction (OER). Using the thermodynamically more favorable hydrazine oxidation reaction (HzOR) to replace OER has attracted ever‐growing attention. Herein, we report a twisted NiCoP nanowire array immobilized with Ru single atoms (Ru1−NiCoP) as superior bifunctional electrocatalyst toward both HzOR and hydrogen evolution reaction (HER), realizing an ultralow working potential of −60 mV and overpotential of 32 mV for a current density of 10 mA cm−2, respectively. Inspiringly, two‐electrode electrolyzer based on overall hydrazine splitting (OHzS) demonstrates outstanding activity with a record‐high current density of 522 mA cm−2 at cell voltage of 0.3 V. DFT calculations elucidate the cooperative Ni(Co)−Ru−P sites in Ru1−NiCoP optimize H* adsorption, and enhance adsorption of *N2H2 to significantly lower the energy barrier for hydrazine dehydrogenation. Moreover, a self‐powered H2 production system utilizing OHzS device driven by direct hydrazine fuel cell (DHzFC) achieve a satisfactory rate of 24.0 mol h−1 m−2. [ABSTRACT FROM AUTHOR]

Metal-free rapid access to pyrrole-2,3-dione has been developed under mild conditions from easily available materials, which was utilized to synthesize pyrrolo[2,3-d]pyridazin-7-one's and pyrrolo[2,3-d]pyrizidines. The overall two-pot process proceeds through (i) the first pot, metal-free direct Mannich reaction-oxidative aromatization of succinaldehyde with C-acyl imine in situ generated to pyrrole-2,3-dione, and (ii) the second pot, further condensation with various hydrazines to synthesize several pyrrolo-pyrizidinones and pyrrolo-pyrizidines in moderate to good yields. [ABSTRACT FROM AUTHOR]

This work presents a comparative experimental and theoretical study on the use of polyaniline and its derivative, poly o‐toluidine, as effective electrochemical sensor for the detection of hydrazine. Hydrazine is a toxic analytic with numerous adverse health effects on the human brain, liver and nervous system. The conducting polymers polyaniline (PANI) and poly o‐toluidine (POT) were synthesized by oxidative polymerization and characterized through x‐ray Diffraction, FT‐IR, and UV–Visible Spectroscopy. Electrochemical studies performed on the polymer modified glassy carbon electrode (GCE) using cyclic voltammetry and differential pulse voltammetry reveal strong interaction between hydrazine and the polymer through irreversible charge transfer. The oxidation current was seen to increase with increasing hydrazine concentration. The diffusion coefficients were found to be 1.89 × 10−5 cm2/s and 2.89 × 10−6 cm2/s for PANI and POT, respectively. PANI and POT based sensors show a limit of detection of 1 μM and 5.13 mM, respectively in the linear concentration range of 1–9 mM. Density functional studies on the PANI‐hydrazine and POT‐hydrazine complexes show enhanced intermolecular charge transfer from nitrogen lone pairs in hydrazine to the polymer backbone clearly identifying the donor and acceptor moieties. PANI based electrochemical sensor is shown to have a higher sensitivity for hydrazine compared to POT, where the sensing interaction is hindered by the bulky methyl group in ortho position. [ABSTRACT FROM AUTHOR]

In this work, we report the biosynthesis of CuCo2S4 nanoparticles (Bio‐NPs) via hydrothermal method. The synthetized Bio‐NPs‐CuCo2S4 was studied as an active material of working electrode for electrochemical supercapacitor and non‐enzymatic hydrazine sensor. The Bio.NPs‐CuCo2S4/ITO electrode has a specific capacitance of 264 F/g at a current density of 1 A/g. Meanwhile, the electrode exhibits excellent electrochemical performances, such as an energy density of 33 Wh/Kg and a power density of 900 W/Kg. The Bio.NPs‐CuCo2S4/ITO electrode for non‐enzymatic hydrazine sensor exhibits a very high sensitivity of 2400 μA.mM−1.cm−2, a wide linear range from 0.001 to 1.400 mM and shows an excellent selectivity. [ABSTRACT FROM AUTHOR]

Reaction of acyl isothiocyanates of 2-allyl- and 2-benzylmaleopimarimides with 3-carboxy- and 2,4-dinitrophenylhydrazines and hydrazides of some aromatic acids (benzoic, 4-hydroxy- and 4-methoxybenzoic, nicotinic, isonicotinic) furnished linear hydrazinocarbonothioyl derivatives of these maleopimarimides in high yields. Structure of the synthesized compounds was determined by 1H,13C, 1H–13C HSQC, 1H–13C HMBC, COSY, NOESY, and 1H–15N HMBC NMR spectroscopy methods. [ABSTRACT FROM AUTHOR]

Inhibiting α‐glucosidase is a reliable method for reducing blood sugar levels in diabetic individuals. Several novel chromen‐linked hydrazine carbothioamide (3a–r) were designed and synthesized by condensation of chromone‐3‐carbaldehyde with a variety of substituted thiosemicarbazides. The structures of these new analogues were elucidated through various advanced spectroscopic techniques (1H NMR, 13C NMR, and ESI‐MS). The resulted compounds were screened for α‐glucosidase inhibitory potential and all the compounds (3a–r) exhibited potent inhibition of α‐glucosidase with IC50 values ranging 0.29–53.70 µM. Among them compounds 3c, 3f, 3h, and 3r displayed the highest α‐glucosidase inhibitor capability with IC50 values of 1.50, 1.28, 1.08, and 0.29 µM, respectively. Structure–activity relationship showed that different substituted groups are responsible for the variation in the α‐glucosidase inhibition. The kinetics studies of the most active inhibitor (3r) were performed, to investigate the mode of inhibition and dissociation constants (Ki), that indicated a competitive inhibitor with Ki value of 1.47 ± 0.31 µM. Furthermore, molecular docking studies was performed to reveal the possible interactions, such as H‐bonding, or π–π stacking, with the key residues of α‐glucosidase. Docking analysis revealed the importance of hydrazine carbothioamide moiety of compounds in the attachment of ligands with the crucial residues of α‐glucosidase. The estimated pharmacokinetic, physicochemical, and drug likeness properties of compounds 3a–r reflects that these molecules have acceptable range of these properties. [ABSTRACT FROM AUTHOR]

Synthesis of some new coordination complexes of main group metals (Ba, Ca, Mg, Sr, and Pb) with 2‐mercaptopyridine‐3‐carboxylic acid (H2Mpc) and hydrazine mixed ligands and their characterization through various chemical and spectral analyses are described in this article. With the help of analytical data obtained from mass, elemental (CHNS), hydrazine content, and metal content analysis, the molecular formulae of the complexes have been proposed as [Ba(N2H4)2(HMpc)H2O], [Ca(N2H4)2(HMpc)(H2O)2], [Sr(N2H4)(HMpc)(H2O)3], [Mg(N2H4)4(HMpc)].4H2O and [Pb(N2H4)5(HMpc)2]. The vibrational (FT‐IR and Raman) spectral data exposes that the 2‐mercaptopyridine‐3‐carboxylic acid coordinates with metal ion via both carboxylate‐O and thiolate‐S in the mode of bi‐dentate dianion while the hydrazine acts as bridging bi‐dentate. On thermal decomposition, these complexes dehydrate to give metal 2‐mercaptopyridine‐3‐carboxylate intermediates, which on further decomposition (heating upto 750°C) give the metal carbonates in the cases of Ba, Ca and Sr, and metal oxides for Mg and Pb. The in vitro antibacterial and antifungal activity of the ligand and its complexes are studied against five bacteria (Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa and Escherichia coli) and four fungi (Candida albicans, Aspergillus niger, Aspergillus fumigatus, and Penicilium variance). [ABSTRACT FROM AUTHOR]

The titled compound, 1,2-bis(2-ethoxybenzylidene) hydrazine was developed using the reaction of 2-ethoxybenzaldehyde and hydrazine monohydrate in an ethanolic solution. In the Schiff-based hydrazine compound, C18H20N2O2, the mid-point of the nitrogen atoms of the central hydrazine moiety is located in inversion symmetry. In C18H20N2O2, C−H···N hydrogen bond linked the molecules, and the framework stabilized by weak C−H···π and π···π stacking interactions. MEP, HOMO and LUMO analysis were performed with the DFT/B3LYP method and the 6-311+G(d,p) basis set. The energies of frontier orbitals were calculated to understand specific molecular properties such as electronegativity, chemical reactivity, chemical hardness and softness. For investigating the contributions of various intermolecular contacts within the hydrazine compound, Hirshfeld surface analysis was performed. The largest contribution of the compound to the main interactions comes from the H···H (64%), C···H (16%) and N···H (9%) interactions. [ABSTRACT FROM AUTHOR]

An efficient synthesis of (13α)-estrone derivatives containing pyran, isoxazole, or pyrazole moieties on the A-ring was performed based on difluoroborate complexes using the chelate methodology. Difluoroborate complexes were synthesized from (13α)-2-acetyl-3-hydroxyestra-1(10),2,4-trien-17-one. [ABSTRACT FROM AUTHOR]

In the present study, ZnMnFeO4 and CoMnFeO4 tri-metallic spinel oxide nanoparticles (NPs) were provided using hydrothermal methods. The nanoparticles have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and electrochemical techniques. A reliable and reproducible electrochemical sensor based on ZnMnFeO4/CoMnFeO4/FTO was fabricated for rapid detection and highly sensitive determination of hydrazine by the DPV technique. It is observed that the modified electrode causes a sharp growth in the oxidation peak current and a decrease in the potential for oxidation, contrary to the bare electrode. The cyclic voltammetry technique showed that there is high electrocatalytic activity and excellent sensitivity in the suggested sensor for hydrazine oxidation. Under optimal experimental conditions, the DPV method was used for constructing the calibration curve, and a linear range of 1.23 × 10−6 M to 1.8 × 10−4 M with a limit of detection of 0.82 ± 0.09 μM was obtained. The obtained results indicate that ZnMnFeO4/CoMnFeO4/FTO nano sensors exhibit pleasant stability, reproducibility, and repeatability in hydrazine measurements. In addition, the suggested sensor was efficiently employed to ascertain the hydrazine in diverse samples of cigarette tobacco. [ABSTRACT FROM AUTHOR]

Applications of abundant seawater in electrochemical energy conversion are constrained due to the sluggish oxygen evolution reaction and the corrosive chlorine oxidation reaction. Hence, it is imperative to develop an efficient anodic reaction alternative suitable for coupling with the cathodic counterpart. Due to a low thermodynamic oxidation potential, hydrazine oxidation reaction (HzOR) offers a unique pathway to overcome these challenges. Herein, spontaneously in situ reduced atomic scale Pd surface‐confined to electrochemically prepared layered Co(OH)2 on carbon cloth is synthesized. This study reveals the hydrazine and Pd‐dependent morphological evolution of Co(OH)2 and its Pd hybrids into nanoparticulate form. Unlike various layered double hydroxides, Pd integrated Co(OH)2 benefits from the contribution of Co(OH)2 as an active HzOR catalyst and the reductive support to host Pd, resulting in synergistically improved performances. Mass activities of Pd in alkaline and alkaline saline electrolyte are 11.24 and 9.83 A mgPd−1 at 200 mV, respectively, corresponding to the highest HzOR activities among noble metals. The optimized Pd hybrid demonstrates ≈6.5 times the current density relative to PtC (14.91 mA cm−2 at 200 mV) in alkaline saline water with hydrazine. These findings would be beneficial to realize high overpotential anodic alternatives and reduce over‐dependence on freshwater for electrocatalysis. [ABSTRACT FROM AUTHOR]

Hydrazine is a promising energy carrier of high power density, high theoretical cell voltage, and zero carbon emission to replace fossil fuel-dominated energy sources. Herein, we present a new Ni–B–P/NF catalyst for hydrazine electrooxidation by a facile electroless plating process. The Ni–B–P/NF catalyst exhibits remarkable catalytic activity (290 mA cm−2 at 0.3 V) by combining merits of high intrinsic activity, large specific surface area, satisfactory conductivity, and lattice dislocation. Meanwhile, the Ni–B–P/NF catalyst provides excellent long-term durability (5000 s, 94.4%), which is at the leading level among the reported Ni-based electrocatalysts for hydrazine electrooxidation to date. It is found that the phosphorus-containing coating and its tight binding to the substrate contribute to the long-term durability of Ni–B–P/NF. XPS results and electron models are used to elucidate the electron transition mechanism of the Ni–B–P coating. This work presents a novel catalyst for hydrazine electrooxidation and demonstrates its promising application in energy storage and fuel cell systems. • The Ni–B–P/Ni foam was prepared by a facile electroless plating process. • The intrinsic active sites, specific surface area, conductivity and lattice dislocation affect the catalytic activity. • The oxidation resistance and bonding ability affect the durability. • The electron transference from Ni atoms to P atoms avoids the formation of Ni 3 (BO 3) 2 and improves the catalytic activity. [ABSTRACT FROM AUTHOR]

Herein, we report the regioselective one‐pot synthesis of 1,4,5‐trisubstituted pyrazoles by reacting Morita‐Baylis‐Hillman (MBH) acetates derived from aryl aldehydes with alkyl or aryl hydrazines in the presence of iodine under aerobic conditions. The reaction proceeds through sequential SN2′ nucleophilic substitution of substituted hydrazine onto the MBH acetate, I2‐catalyzed oxidation of the allylic hydrazine to allylic hydrazone, heating‐induced intramolecular aza‐Michael reaction and cyclization, and oxidative aromatization. The key intermediate, the s‐trans allyl hydrazones were isolated in good yields by performing the reactions at room temperature. However, the allyl hydrazones prepared from the MBH acetates of aliphatic aldehydes did not furnish the pyrazole owing to the absence of an activated methylene group in the substrate. The synthetic applications of the pyrazoles in Ugi reactions, decarboxylative halogenation, Pd‐catalyzed benzoylation of the N‐aryl ring, and metal‐free tetrazole synthesis has been demonstrated. [ABSTRACT FROM AUTHOR]

Traditionally, toxic and expensive hydrazine building blocks are required to construct pharmaceutically important pyrazolidine-3,5-diones. Herein, we have described a novel method for their synthesis based on metal-free oxidative dehydrogenative N–N bond formation by PIDA-mediated reaction of easily accessible dianilide precursors. The developed mild reaction protocol features a good functional group tolerance and scalability. The application of this method is demonstrated by offering a unique route for the synthesis of uricosuric agents G-25671 and sulfinpyrazone from inexpensive starting material aniline via smooth functionalization of the well-designed diversity-oriented cyclopropyl key intermediate. [ABSTRACT FROM AUTHOR]

Methanol was used as a solvent to perform a one-pot direct oxidation of tetrahydrocarbazoles with periodic acid, followed by regioselective iodination. The oxidative iodination products, substituted 3-iodo-1,2,3,4-tetrahydro-9H-carbazol-1-ones, were obtained in 60–82% yields. Initial tetrahydrocarbazole derivatives were prepared from cyclohexanone and substituted phenyl hydrazines. [ABSTRACT FROM AUTHOR]

Hydrazone compounds represent an important area of research that includes, among others, synthetic approaches and biological studies. A series of 17 hydrazones have been synthesized by mechanochemical means. The fragments chosen were phenolic and furanyl aldehydes coupled with 12 heterocyclic hydrazines or hydrazinamides. All compounds can be obtained quantitatively when operating on a planetary ball mill and a maximum reaction time of 180 min (6 cycles of 30 min each). Complete spectroscopic analyses of hydrazones revealed eight compounds (3–5, 8–11, 16) present in one geometric form, six compounds (1, 2, 13–15) present in two isomeric forms, and three compounds (6, 7, 12) where one rotation is restricted giving rise to two different forms. The single crystal X-ray structure of one of the hydrazones bearing the isoniazid fragment (8) indicates a crystal lattice consisting of two symmetry-independent molecules with different geometries. All compounds obtained were tested for anti-infectious and antibacterial activities. Four compounds (1, 3, 5 and 8) showed good activity against Mycobacterium tuberculosis, and one (7) was very potent against Staphylococcus aureus. Most interesting, this series of compounds displayed very promising antileishmanial activity. Among all, compound 9 exhibited an IC50 value of 0.3 µM on the Leishmania donovani intramacrophage amastigote in vitro model and a good selectivity index, better than miltefosine, making it worth evaluating in vivo. [ABSTRACT FROM AUTHOR]

Purpose: A novel semiconducting macromolecule-polyperylene tetraamide (PPTI) was first synthesized with a simple method using 3, 4, 9, 10-perylene tetracarboxylic acid (PTCA) and hydrazine hydrate (N2H4). Design/methodology/approach: The Ag nanoparticle was doped on the surface or inside of the PPTI film to obtain a highly sensitive hydrazine sensor-Ag/PPTI, which was synthesized within one step. The structure of Ag/PPTI was characterized through various techniques such as Fourier transform infrared (FT-IR), thermogravimetric analyzer (TGA), X-ray diffraction (XRD), X-ray photoelectron spectroscopy measurements (XPS) and scanning electronic microscopy (SEM). Findings: According to cyclic voltammetry results, Ag/PPTI/GCE indicated good electrocatalytic activity toward the oxidation of hydrazine. The amperometric detection of hydrazine was then applied on Ag/PPTI/GCE. It exhibited a wide linear range from 0.05 to 50 µM, a low detection limit (S/N = 3) of 0.05 µM and high sensitivity of 0.45 µA/(µM•cm2). Originality/value: In authors' perception, this approach emerges as an effective technique for developing efficient chemical sensors for environmental pollutants. [ABSTRACT FROM AUTHOR]

Releasing unsymmetrical dimethyl hydrazine (UDMH) in ambient medium is an escalating environment crisis that catches aggrandizing public concerns. Herein, a non-thermal plasma activating persulfate maneuver was introduced and its application mechanism in UDMH degradation was explored. Oxidizing kinetic experiments show that 93.8% UDMH were eliminated along with 12.5 kV, pH = 8, 50 mM NaCl, Na2S2O8/UDMH (mol/mol) = 2, and 140 mL/min. The Visual MINTEQ simulated species distribution of UDMH well predicted the oxidation behaviors of UDMH in the variation of pH. Radical scavenging test integrated with UV-vis spectroscopy were introduced to identify the predominating reactive oxygen species during UDMH decomposition. The ·OH and ·SO4 - played a synergistic role in the UDMH oxidization. Overall, this study may shed new lights on the degradation of UDMH industry wastewater using hybrid technique. [ABSTRACT FROM AUTHOR]

INTRODUCTION: I nhalation of hydrazine or hydrazine-derivative (for example, monomethylhydrazine) vapors during spaceflight operations remains a risk to crew and ground support personnel. Here we sought to provide an evidence-based approach to inform acute clinical treatment guidelines for inhalational exposures during a noncatastrophic contingency spaceflight recovery scenario. METHODS: A review of published literature was conducted concerning hydrazine/hydrazine-derivative exposure and clinical sequelae. Priority was given to studies that described inhalation though studies of alternative routes of exposure were additionally reviewed. Where possible, human clinical presentations were prioritized over animal studies. RESULTS: Rare human case reports of inhalational exposure and multiple animal studies provide evidence of varied clinical sequelae, including mucosal irritation, respiratory concerns, neurotoxicity, hepatotoxicity, hemotoxicity (including Heinz body development and methemoglobinemia), and longitudinal risks. In an acute timeframe (minutes to hours), clinical sequelae are likely to be limited to mucosal and respiratory risk; neurological, hepatotoxic, and hemotoxic sequelae are unlikely without recurrent, longitudinal, or noninhalational exposure. CONCLUSIONS: Acute clinical management should focus on likely clinical concerns as supported by existing data; recovery medical personnel should be prepared to manage mucosal irritation and respiratory concerns, including the potential need for advanced airway management. There is little evidence supporting the need for acute interventions for neurotoxicity and there is no evidence that acute hemotoxic sequelae would drive the need for on-scene management of methemoglobinemia, Heinz body development, or hemolytic anemia. Training that overemphasizes neurotoxic or hemotoxic sequelae or specific treatments for such conditions potentially raises the risk for inappropriate treatment or operational fixation. [ABSTRACT FROM AUTHOR]

Mutagenesis is a highly efficient tool for establishing genetic variation and is widely used for genetic enhancement in various plants. The key benefit of mutation breeding is the prospect of enhancing one or several characteristics of a variety without altering the genetic background. In this study, we exposed the seeds of Salvia officinalis to four concentrations of hydrazine hydrate (HZ), i.e., (0%, 0.1%, 0.2%, and 0.3%) for 6 h. The contents of terpenoid compounds in the S. officinalis plantlets driven from the HZ-treated seeds were determined by GC-MS, which resulted in the identification of a total of 340 phytochemical compounds; 163 (87.48%), 145 (84.49%), 65 (97.45%), and 62 (98.32%), from the four concentrations of HZ (0%, 0.1%, 0.2%, and 0.3%), respectively. Furthermore, we used the qRT-PCR system to disclose the "transcriptional control" for twelve TPS genes related to terpenoid and terpene biosynthesis, namely, SoGPS, SoMYRS, SoNEOD, SoCINS, SoSABS, SoLINS, SoFPPS, SoHUMS, SoTPS6, SoSQUS, SoGGPS, and SoGA2. Altogether, results are likely to ensure some positive relationship between the concentrations of the chemical mutagen HZ used for treating the seeds, the type and amount of the produced terpenes, and the expression of their corresponding genes. [ABSTRACT FROM AUTHOR]

Here, we report a class of ligands based on oxalohydrazide cores and N-amino pyrrole and N-amino indole units that generates long-lived copper catalysts for couplings that form the C-O bonds in biaryl ethers. These Cu-catalyzed coupling of phenols with aryl bromides occurred with turnovers up to 8000, a value which is nearly two orders of magnitude higher than those of prior couplings to form biaryl ethers and nearly an order of magnitude higher than those of any prior copper-catalyzed coupling of aryl bromides and chlorides. This ligand also led to copper systems that catalyze the coupling of aryl chlorides with phenols and the coupling of aryl bromides and iodides with primary benzylic and aliphatic alcohols. A wide variety of functional groups including nitriles, halides, ethers, ketones, amines, esters, amides, vinylarenes, alcohols and boronic acid esters were tolerated, and reactions occurred with aryl bromides in pharmaceutically related structures.

Proteasome inhibitors, such as bortezomib and carfilzomib, have shown efficacy in anti-cancer therapy in hematological diseases but not in solid cancers. Here, we found that liposarcomas (LPS) are susceptible to proteasome inhibition, and identified drugs that synergize with carfilzomib, such as selinexor, an inhibitor of XPO1-mediated nuclear export. Through quantitative nuclear protein profiling and phospho-kinase arrays, we identified potential mode of actions of this combination, including interference with ribosome biogenesis and inhibition of pro-survival kinase PRAS40. Furthermore, by assessing global protein levels changes, FADS2, a key enzyme regulating fatty acids synthesis, was found down-regulated after proteasome inhibition. Interestingly, SC26196, an inhibitor of FADS2, synergized with carfilzomib. Finally, to identify further combinational options, we performed high-throughput drug screening and uncovered novel drug interactions with carfilzomib. For instance, cyclosporin A, a known immunosuppressive agent, enhanced carfilzomib's efficacy in vitro and in vivo. Altogether, these results demonstrate that carfilzomib and its combinations could be repurposed for LPS clinical management.

Reported here is the Pd-catalyzed C-N coupling of hydrazine with (hetero)aryl chlorides and bromides to form aryl hydrazines with catalyst loadings as low as 100 ppm of Pd and KOH as base. Mechanistic studies revealed two catalyst resting states: an arylpalladium(II) hydroxide and arylpalladium(II) chloride. These compounds are present in two interconnected catalytic cycles and react with hydrazine and base or hydrazine alone to give the product. The selectivity of the hydroxide complex with hydrazine to form aryl over diaryl hydrazine was lower than that of the chloride complex, as well as the catalytic reaction. In contrast, the selectivity of the chloride complex closely matched that of the catalytic reaction, indicating that the aryl hydrazine is derived from this complex. Kinetic studies showed that the coupling process occurs by rate-limiting deprotonation of a hydrazine-bound arylpalladium(II) chloride complex to give an arylpalladium(II) hydrazido complex.

[Display omitted] Reaction between tetracyanoethylene and N,N -dimethyl-or N -(2-pyridyl)hydrazines affords 5-amino-3,4-dicyano-pyrazoles. In cases of aromatic amines, replacement of one cyano group by amino one occurs thus giving N -(tricyano-vinyl)anilines. [ABSTRACT FROM AUTHOR]

Abstract A theoretical analysis of free Gibbs Energy and NMR 1H 13C chemical shifts of the effect of introduce methyl groups on diphenyl rings, to produce different isomers of (E)-1-(α,Ꞵ-dimethylbenzylidene)-2,2-diphenylhydrazine, is presented. IR vibrational frequencies, Mulliken charges, molecular electrostatic potential (MEP), Gibbs free energy (G) and 1H- and 13C-NMR chemical shifts were obtained by theoretical calculations. In this analysis it was found that the position of the methyl group affects the values of the 1H- and 13C-NMR chemical shifts and the ∆G and ∆H thermodynamic properties of formation and reaction, these properties vary with the same trend, for the isomers studied. Gibbs free energy calculations show that the theoretical (E)-1-(3,4-Dimethylbenzylidene)-2,2-diphenylhydrazine isomer is the most stable, which explains the success of the experimental synthesis of this compound among the other isomers. For this molecule, the C of the HC=N group is the most nucleophilic and the H is the least acidic. The 1H-NMR chemical shifts of protons show a strong correlation with the C=N distance. It was also observed that methyl affects the ν(C=N) frequencies, the C=N distance increases when the inductive effect of the methyl groups is in the structure.

Exploring synthetic methods and catalysts that are easy to handle, highly active, and low-cost for producing industrially important chemicals is a long-term goal in both science and industry. Herein, we present a general and facile Ni-catalyzed reductive amination of aldehydes/ketones methodology using hydrazine as both nitrogen and hydrogen sources, instead of the traditionally used hydrogen gas and ammonia. The mesostructured alumina-supported Ni catalyst with a relatively high ratio of Ni0 and small-sized Ni nanoparticles plays a critical role in this transformation, resulting in 55 aldehydes/ketones successfully converting to their corresponding primary amines with 61–99% yields. This work outlines a low-cost yet robust catalytic methodology for the facile and general synthesis of primary amines for practical laboratory and industrial application. [ABSTRACT FROM AUTHOR]

Constructing low cost and efficient electrochemical sensors for highly sensitive detection of hydrazine has a great significance in the field of environmental monitoring and protection. Herein, metal–organic framework derived Co3S4 nanosheets grown on Ti mesh (Co3S4/TM) were successfully synthesized by employing a facile anion exchange reaction and hydrothermal vulcanization with Co-MOF as the precursor. The crystalline structure and morphology of as-synthesized samples were characterized by XRD, SEM, Raman, XPS and TEM analysis. It was found that Co3S4 nanosheets were stacked loosely and irregularly on each other to form a three-dimensional (3D) porous structure. The electrochemical sensing performance of Co3S4/TM toward hydrazine was investigated in 0.1 M NaOH solution. The results showed that Co3S4/TM presented a better electrocatalytic activity toward hydrazine oxidation than Co-MOF/TM and Co(OH)2/TM, owing to the high electrical conductivity of Co3S4 for enhancing electron transfer and the 3D porous structure for providing many more accessible active sites and shortening ion diffusion length as well as promoting mass transfer for hydrazine electrooxidation. As a result, Co3S4/TM exhibited a superior analytical performance with a wide linear range of 0.005–2.0 mM, a high sensitivity of 2956 μA mM−1 cm−2 and a low detection limit of 0.7 μM (S/N = 3), which was superior or comparable to that of the recently reported sensor. Because of the good selectivity and reproducibility, Co3S4/TM was applied to detection of hydrazine in tap water and it showed good recovery, indicating that it could be a promising candidate for analyzing hydrazine in practical application. [ABSTRACT FROM AUTHOR]

The development of efficient and cost-effective electrocatalysts for hydrogen evolution is a need of time. Because hydrogen is superior to other natural energy sources owing to its high energy density of 120 to 140 MJ kg−1. Therefore, scientists have been working on a low oxidation potential needed hydrazine oxidation technique to produce hydrogen in place of the slow oxygen evolution mechanism. Direct hydrazine fuel cells (DHFCs) are promising as portable or vehicular power sources; nonetheless, they need the development of low-cost, efficient anodic hydrazine oxidation catalysts (HzOR). Herein, we have prepared zinc-doped oxygen-deficient nickel cobalt oxide (Zn-NiCoO x-z) alloy nanoarray on stainless steel mesh (SSM) using a hydrothermal method followed by thermal reduction treatment. The overall hydrazine splitting potential (OHzS) required to achieve 50 mA cm−2 in a two-electrode system (Zn-NiCoO x-z /SSM(-)∥Zn-NiCoO x-z /SSM(+)) is only 0.700 V, which is much less than the required potential for overall water splitting (OWS). [Display omitted] Hydrogen has a high energy density of approximately 120 to 140 MJ kg−1, which is very high compared to other natural energy sources. However, hydrogen generation through electrocatalytic water splitting is a high electricity consumption process due to the sluggish oxygen evolution reaction (OER). As a result, hydrogen generation through hydrazine-assisted water electrolysis has recently been intensively investigated. The hydrazine electrolysis process requires a low potential compared to the water electrolysis process. Despite this, the utilization of direct hydrazine fuel cells (DHFCs) as portable or vehicle power sources necessitates the development of inexpensive and effective anodic hydrazine oxidation catalysts. Here, we prepared oxygen-deficient zinc-doped nickel cobalt oxide (Zn-NiCoO x-z) alloy nanoarrays on stainless steel mesh (SSM) using a hydrothermal synthesis method followed by thermal treatment. Furthermore, the prepared thin films were used as electrocatalysts, and the OER and hydrazine oxidation reaction (HzOR) activities were investigated in three- and two-electrode systems. In a three-electrode system, Zn-NiCoO x-z /SSM HzOR requires −0.116 V (vs RHE) potential to achieve a 50 mA cm−2 current density, which is dramatically lower than the OER potential (1.493 V vs RHE). In a two-electrode system (Zn-NiCoO x-z /SSM(-)∥Zn-NiCoO x-z /SSM(+)), the overall hydrazine splitting potential (OHzS) required to reach 50 mA cm−2 is only 0.700 V, which is dramatically less than the required potential for overall water splitting (OWS). These excellent HzOR results are due to the binder-free oxygen-deficient Zn-NiCoO x-z /SSM alloy nanoarray, which provides a large number of active sites and improves the wettability of catalysts after Zn doping. [ABSTRACT FROM AUTHOR]

Density functional theory has been used to elucidate the mechanistic underpinnings of the regeneration of ammonia‐borane (H3B−NH3, AB) from polyborazylene (BxNxHx, PBz) in the presence of hydrazine (H2N−NH2, Hz). Herein, borazine (B3N3H6, Bz) is used as the simplest relevant model of PBz for the regeneration process. Digestion of Bz using Hz was found to occur by a string of Lewis acid base adduct (between B atoms of Bz and Hz molecule) formation and Hz assisted proton transfer processes. Later, B−H bonds of HB(NHNH2)2, the Bz digested product, are redistributed to form hydrazine‐borane (H3B−NH2NH2, HzB) and B(NHNH2)3. Redistribution of B−H bonds occurs through hydroboration and concerted proton‐hydride transfer. Another B−H redistributed product, B(NHNH2)3, produces HzB as a result of proton and hydride transfer from cis‐diazene (Dz), the oxidized product of Hz in presence of O2. [ABSTRACT FROM AUTHOR]

A highly sensitive analytical method has been developed for trace level quantification of formaldehyde in active pharmaceutical ingredient. Formaldehyde is a highly toxic impurity. Determination of formaldehyde by using UV-visible spectroscopy is difficult due to interference of unreacted derivatizing agent; hence, either HPLC-UV or GC-MS are used for the quantification. However, we have developed an indirect method for the quantification of formaldehyde. In this method, in the first step, formaldehyde reacted with excess of 2,4-dinitrophenyl hydrazine (2,4-DNPH). In the second step, the quantification of unreacted 2,4-DNPH was done by detecting its derivative with its scavenger—cinnamaldehyde on a UV-visible spectrophotometer. The developed method is rapid, simple, sensitive and accurate for the quantification of formaldehyde. Linearity of the method was observed in the range of 0.5–3 μg/mL with determination coefficients (r2) > 0.999. The limit of detection and limit of quantification are 0.25 and 0.5 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

The condensation of 4,4-dichlorobut-3-en-2-one with aromatic aldehydes in the presence of a cata-lytic amount of sulfuric acid afforded 1,1-dichloro-5-(4-R-phenyl)penta-1,4-dien-3-ones which reacted with substituted hydrazines under mild conditions in chemo- and regioselective fashion to give 3-[(E)-2-arylethenyl]-5-chloro-1-methyl-1H-pyrazoles in up to 81% yield. The reaction of 4-bromo-1,1-dichloro-5-(4-methoxy-phenyl)-penta-1,4-dien-3-one with N,N-dimethylhydrazine produced 3-[1-bromo-2-(4-methoxyphenyl)-ethenyl]-5-chloro-1-methyl-1H-pyrazole which was converted to 5-chloro-3-[(4-methoxyphenyl)-ethynyl]-1-methyl-1H-pyrazole in 69% yield on heating in DMSO in the presence of KF at 120°C. The structure of the synthesized compounds was confirmed by IR, NMR, and mass spectra and elemental analyses. [ABSTRACT FROM AUTHOR]